The 50-year old concept of an evolutionarily stable strategy provided a key tool for theorists
to model ultimate drivers of behaviour in social interactions. For decades, economists …

We describe a formal model of norm psychology that can be applied to better understand
norm change. The model integrates several proximate drivers of normative behavior: beliefs …

Repeated interactions provide an evolutionary explanation for one-shot human cooperation
that is counterintuitive but orthodox,–. Intergroup competition,,–provides an explanation that …

Social stigma can effectively prevent people from going out and possibly spreading COVID-
19. Using the framework of replicator dynamics, we analyze the interaction between self …

There are two broad functional explanations for second-party punishment: fitness-leveling
and deterrence. The former suggests that people punish to reduce fitness differences, while …

Theory suggests that a form of Kantian morality has evolutionary foundations. To investigate
the relative importance of Kantian morality and social preferences, we run a laboratory …

To resolve the major controversy about why prosocial behaviors persist in large‐scale
human societies, we propose that two questions need to be answered. First, how do social …

From protists to primates, intergroup aggression and warfare over resources have been
observed in several taxa whose populations typically consist of groups connected by limited …

Hamilton's rule [WD Hamilton, Am. Nat. 97, 354–356 (1963); WD Hamilton, J. Theor. Biol. 7,
17–52 (1964)] quantifies the central evolutionary ideas of inclusive fitness and kin selection …

Many social interactions happen indirectly via modifications of the environment, eg through
the secretion of functional compounds or the depletion of renewable resources. Here, we …